Many devices and systems include circuits that are designed based on target performance characteristics. Unfortunately, these circuits may not always meet these targets. For example, effects such as process variations during manufacturing, variations in a power supply voltage, variations in temperature, or even aging of a component may result in a distribution of performance characteristics, some of which may fall below the targets.
In the case of input/output (I/O) interfaces, a failure to achieve a target data rate often results in a complete failure of the device or system that includes the interface. An inability to adapt the data rate or to adjust one or more circuit parameters to achieve a desired data rate may, therefore, have consequences for overall yield, cost, lifespan and the reliability of the devices or systems.
There is a need, therefore, for improved I/O interfaces whose data rate may be adapted or adjusted without the aforementioned problems.
Like reference numerals refer to corresponding parts throughout the drawings.